1. Fit people tend to sweat more and sooner than unfit people. Their bodies are more efficient at cooling.

2. When people start training as a result of a New Year's Resolution, 60% have quit by Valentine's Day.

3. If your workout clothes smell like ammonia after a workout, you're burning a lot of protein for fuel. Ammonia is a byproduct of protein metabolism. This is not a good thing, as burning protein means you may be burning your muscle tissue for energy instead of carbohydrates or bodyfat.

4. Men tend to overestimate their strength while women tend to underestimate their strength.

5. To determine if your scale is correct, set a dumbell or a weight plate on it. If the numbers don't match, try another weight and see if it's off by the same amount. Adjust your scale accordingly.

6. Sometimes a barbell exercise causes pain while the dumbell version doesn't. This occurs most often with the bench press and the shoulder press. Dumbell don't lock your joints into a certain pattern of movement.

7. There is no evidence to support the argument that machines are safer than free weights, according to studies.

11. Acclimation to exercising in the heat can take about 10 to 14 days. For each two days of not exercising in heat, one day of acclimation is lost.

12. There is an indirect effect on other muscles when you work a muscle. The bigger the muscle, the greater the carryover. This is one reason you should not neglect leg training as the largest muscles in the body are found in the legs and will have the greatest impact on the rest of your body.

13. The initial adaptation to weight training is neuromuscular (in the nervous system). Your muscles are basically learning how to fire efficiently. This is why beginning trainers are often very shaky when they first start lifting weights. Their muscles haven't learned how to activate properly.

14. Holding your breath during an exercise to temporarily increase intra-abdominal pressure is called the Valsalva maneuver. While it can be effective in temporarily increasing strength and stability, it can be very dangerous, especially if you have high blood pressure. It is, with few exceptions, better to breathe while lifting.

15. Training intensity is properly measured as a percentage of a person's One Rep Max (the most weight they can lift for a single rep). A high intensity means a high percentage. It is technically not a subjective measure of effort or facial expression.

16. The best performances in strength competitions are seen in the afternoon and early evening. This may be due to increased muscle temperature later in the day. A lower temperature may increase endurance however. Endurance training may therefore be more effective when done in the morning.

17. Shorter rest periods (less than 1 minute) will result in an increase in the hormones related to muscle growth. However, lower rest periods will result in decreased strength during your workout. You will get hypertrophy (muscle growth) at the expense of strength.

18. The intestine is the single largest receptor of Growth Hormone in the body. This is why people who take frequent Growth Hormone injections often have distended (bloated) abdomens. Natural levels of Growth Hormone don't result in this effect.

19. After a high volume of aerobic work, fast-twitch muscle fibers (the larger more powerful fibers) can act like slow-twitch muscle fibers (the smaller, more endurance-oriented fibers). This doesn't work the other way, though. If your goal is to gain muscle, decrease the frequency of your aerobic work. The converted fast-twitch muscles can revert to their original form after about 4 to 8 months of aerobic detraining.

20. The hormone Insulin signals the body that there is enough sugar in the blood to be burned for energy. This prevents the fat cells from releasing fat. The hormone Glucagon, which unlocks fat stores, can't be released when insulin is present.

21. The number of fat cells in our body is predetermined by genetics, however, prolonged overfeeding can cause fat cells to split into more cells, especially during the teen years. The more you have, the more you have available to fill up and the greater your potential for obesity.

22. Men have about 18 times higher levels of testosterone than women. Men with higher natural testosterone levels gain muscle faster. People who have a harder time gaining muscle have lower testosterone levels.

23. The more deficient you are in vitamins and minerals the more of an effect you will notice from supplementation. Be careful not to overdo it and take too much though.

24. Strenuous exercise can double mineral loss. Increased sweating is a major cause of this.

25. Vitamin capsules are generally better than tablets as tablets can be compressed so hard as to be indigestible.

26. Minerals that enhance sleep, recovery, healing, regeneration and growth like zinc and magnesium should be taken on an empty stomach before bed. The body's maximum daily release of Growth Hormone occurs 90 minutes into sleep. Zinc and magnesium may increase the effects of G.H. and peak absorption of these minerals occurs after 90 minutes. Take 20-30 mg of zinc and 400-500mg of magnesium.

27. Sodium and calcium are removed via the same mechanism in the body therefore when you increase your sodium intake, your body strives to maintain balance by excreting more sodium. When 1 molecule of sodium goes, it takes a molecule of calcium with it. This can decrease bone mass in the long term. If you have osteoporosis or wish to prevent it, decrease your sodium intake.

28. Be careful what you eat grapefruit with. Naringin (an enzyme found in grapefruits - also called naringenin) may increase the power of some drugs. It deactivates enzymes in your stomach that normally break down drugs. When mixed with alcohol, test subjects ended up with four times more alcohol in the blood.

30. Many people are overweight because they are malnourished. Their body craves nutrients so they are hungry. What they eat doesn't supply the nutrients they need so they are still hungry. Empty-calorie food is the culprit.

31. 20% of the calories in protein are used for digestion and assimilation. 8% of the calories of carbs are used. The number is only 2% for fat.